Bulldozer tractor



Jan. 19, 1960 Filed Feb. 16, 1956 H. H. BIDWELL 2,921,392

BULLDOZER TRACTOR 2 Sheets-Sheet 1 WWKLV amp/Mali 4 Mom/w 9f. @hdw/afl /02 97 11 M {M 99 Mona W3 Jan. 19, 1960 H. H. BIDWELL 2,921,392

BULLDOZEIR TRACTOR 2 Sheets-Sheet 2 43 O I Z2 4' 44 7 6 E II \I United States Patent O BULLDOZER TRACTOR Harry H. Bidwell Springfield Ill. assignor to Allis- Chalmers Manufiicturing Company, Milwaukee, Wis.

Application February 16, 1956, Serial No. 565,908

7 Claims. (Cl. 37-144) This invention relates to a crawler tractor with a dozer blade attachment and is particularly concerned with the mounting structure for the lift mechanism employed to raise and lower the bulldozer blade.

Heretofore it has been customary to install a mounting structure for hydraulic jacks or cable blocks which is secured to the main frame and at each side of the radiator guard with which the usual crawler tractor is equipped. The usual radiator guard with which many crawler tractors are equipped is too light in construction to beused to mount the cable blocks or hydraulic jacks which raise and lower the bulldozer blade. It has been the usual practice to securely bolt the mounting structure for the hydraulic jacks on the channel members of the main frame, these channel members being utilized also to 'mount the engine and its radiator. The mounting structure previously employed for the hydraulic jacks also served to some extent as a guard so as to prevent damage to the radiator, fan and other engine components should boulders or other material rise over the top of the dozer blade during excavating. Heretofore it has been found inconvenient to service and replace front engine components since considerable time and labor was needed to remove the guards prior to servicing. The mounting structures heretofore employed for the cable blocks or jacks were of heavy construction and of considerable weight thereby necessitating the use of a crane or hoist to remove and replace them before and after a replacement operation on the front engine components as for instance a radiator.

It is an object of this invention to provide a combined engine guard and mounting structure for cable sheaves or hydraulic jacks which will take care of the difficulties hereinbefore outlined in an entirely satisfactory manner.

It is a further object of this invention to provide an engine guard affording ease of servicing and replacement and which entirely replaces the usual radiator guard with which tractors are usually equipped.

It is a further object of the invention to provide a guard permitting servicing of the engine without the necessity of separating the guard from the main frame of the tractor.

It is a further object of this invention to provide a guard of the type hereinbefore outlined which serves also to mount the lift mechanism.

It is a further object of this invention to provide an engine guard which is adapted to mount a pair of hydraulic jacks and which may be adjusted to and from an installed position by actuation of the jacks.

These and other objects and advantages of this invention will be apparent from the following description when it is read in conjunction with the drawings, in which:

Fig. 1 shows a side view of a crawler tractor having a cable operated dozer blade connected thereto and wherein the radiator or engine guard for the forward end of the engine supports cable sheaves;

Fig. 2 is a front view of the guard shown in Fig. 1 with portions cut away to show attaching members;

braces 24, 24.

Fig. 3 is a vertical section of the guard and mounting structure shown in Figs. 1 and 2;

Fig. 4 is a section view taken on line IVIV in Fig. 3;

Fig. 5 is a side view showing a second embodiment of the invention wherein the dozer is operated by a pair of hydraulic jacks which are mounted on the guard;

Fig. 6 shows the guard pivoted forwardly by the hydraulic jacks; and 1 Fig. 7 is a section view of the jack mounting taken along line VIIVII in Fig. 6.

Referring to Fig. 1, the crawler tractor 11 has running gear in the form of endless track mechanisms 12 at laterally opposite sides of the tractor main frame 13. These track mechanisms are connected on an axis 14 to the rear end of the main frame 13 of the tractor. An

operators station 16 is provided on the main frame together with appropriate controls for operating the tractor. An engine 17 is mounted at the forward end of the main frame 13 and this engine drives the endless track belts through a transmission mechanism, not shown. For purposes of illustration a rear mounted cable control unit 18 is shown as well as a front mounted cable control unit 19. Only one of these units would be used at any one time to control the operation of the tool 21.

A radiator guard 22 is pivotally connected to the main frame 13 by a pair of pivots 23, 23'. A pair of braces 24, 24' are secured to the main frame, as will be more fully explained hereinafter, and are also attached to the rear edge of side portions of the radiator guard 22. Side panels 27, 27 are connected at their forward ends to A sheave block 28 is pivotally connected to a mounting bracket 29, the latter being secured, as by welding, to the central top portion of the guard 22.

The tool 21 has a pair of push beams 31 disposed at each side of the crawler tractor. The rear ends of the push beams 31 are pivotally connected by pivot pins 32 to truck frames 33 of the endless track mechanisms 12. The tool 21 has a blade 34 rigidly secured to the forward ends of the push beams 31. Although only one push beam 31, one pin 32 and one truck frame 33 are shown in Figs. 1, 5 and 6, it is to be understood that these elements for the opposite hand side of the tractor are reverse images. A sheave block 36 is pivotally connected to the tool 21 and a cable 37 is reeved about the sheaves in the sheave blocks 28 and 36.

-Referring to Figs. 2, 3 and 4, the guard 22 is shown in greater detail. The guard 22 includes a top wall 40, a front wall 41 and side walls 42, 42' all of which are rigidly interconnected, as by welding, or unitary construction. The guard is braced against torsional loads by a pair of transverse beams 43, 44 which are secured, as by welding, to one another and to the side, top and front walls of the guard 22. The guard may be subjected to twisting moments in several situations as, for instance, when the hydraulic rams operating the dozer are unequally loaded. A plurality of air passages 45 are provided in the front wall 41.

- A solid rod 46 is welded to the upper rear edge of each 58 present arcuate recesses which are formed concentrically w1th complementary semicircular cylindrical surfaces 112, 112' of the caps 51, 51' to provide a cylindrical openmg, respectively, in the lower portion of the side- I The semicircular cylindrlcal downward facing surfaces 110, of base 50, v

walls 42, 42'. Caps 51, 51' are secured to the bases 50, 50' of the pivots 23, 23' by cap screws 52, 52. Pivot blocks 53, 53' are secured to the main frame members 54, 54' by bolts 55, 55 and nuts 57, 57'. The pivot blocks 53, 53' have spindle portions 56, 56' fitting into the cylindrical openings provided 'by bases 50, 50' and caps 51, 51. Side panels 27, 27' are secured to the main frame by a plurality of cap screws 62. A solid rod 64 is welded to the upper side of each of the side panels 27, 27' to add rigidity thereto. The stabilizing braces 24, 24' are secured by bolts 66 and nuts 67 at their bottom ends to the main frame members 54, 54'. The stabilizing braces 24, 24 have upright extensions which are bolted to the rear edges of the side walls 42, 42 and the forward edges of the side panels 27, 27' by a plurality of bolts 68 and nuts 69.

From the foregoing description it will be seen that bracket elements 50, 50', spindles or stub shafts 56, 56' and bearing caps 51, 51 are the components of a load transmitting pivot connection between the guard 22 and the tractor main frame 13. The stub shafts 56, 56 which are rigidly mounted, respectively, in axial alignment on the pivot axis at opposite sides of the main frame 13, constitute a pair of lower load transmitting elements presenting convex cylindrically arcuate upward facing bearing surfaces 109, 109, respectively. Bracket elements 50, 50 are in effect, upper load transmitting elements presenting concave arcuate downward facing bearing surfaces 110, 110' which are concentric with the pivot axis and complementary to and rotatably mounted on bearing surfaces 109, 109 of stub shafts 56, 56. Caps 51, 51' present bearing surfaces 112, 112, respectively, being concentric with bearing surfaces 110, 110' and complementary to the lower bearing surfaces of the stub shafts 56, 56'. Caps 51, 51 in effect are releasable means which retain the upper and lower bearing surfaces 109, 109' and 110, 110', respectively, in load bearing relationship with each other. Cap screws 52, 52' are means for detachably fastening caps 51, 51, respectively, on bracket elements 50, 50 in cooperative relationship with stub shafts 56,

Sheave block 28 is pivotally connected on a transverse horizontal axis to bracket 29 by a pin 71. A sheave block 72 is secured, as by welding, to the left hand corner of the guard 22, as viewed in Fig. 2. A pin 73 pivotally mounts a sheave 74 in the sheave block 72. A pair of cable sheaves 76, 77 are pivotally mounted on the side wall 42 by a pair of pivot pins 78, 79, respectively. A conduit 81 is disposed between sheaves 76 and 77 and a conduit 82 is disposed between sheave 77 and the rear mounted cable control unit 18 for the purpose of guiding cable between the sheaves 76 and 77 and between sheave 77 and the rear control unit 18. A hole 83 is provided through the assembly of the upright extension bracket 24', the rear edge of side wall 42 and the front edge of side panel 27 to permit passage of cable therethrough.

When the front mounted power control unit 19 is used to control the dozer 21, the cable passes from sheave block 28 to the sheave 74 and thence to the drum, not shown, on the front control unit 19. When the rear mounted cable control unit 18 is used to control the elevation of the cutting blade of the dozer 21 the cable passes from the sheave block 28 to sheave 74, thence to sheaves 76 and 77 and then to the control unit 18. Between sheaves 76 and 77 the cable passes through tube 81 and between sheave 77 and the control unit 18 the cable passes through hole 83 and tube 82.

Referring to Figs. and 6, a hydraulically operated dozer is shown. The same basic guard shell is used with a hydraulically operated bulldozer as with a cable operated bulldozer, thus saving on production costs. With the basic shell of this guard as standard equipment, either the cable sheaves shown in Figs. 1, 2, 3 and 4 or the hydraulic jacks shown in Figs. 5 and 6 may be installed.

As shown in Figs. 5 and 6, a trunnion 86 is welded t each of the side walls 42, 42. The trunnion has reinforcing wings 87, 88 which lend rigidity to the guard assembly. A cylinder 89 and a piston 91 constitute relative expansible and contractible elements which form a pair of hydraulic jacks 92. These hydraulic jacks 92 are double acting and are provided to raise and lower the tool 21. The hydraulic jacks 92 are supplied with fluid in a conventional manner by a pressure fluid mechanism, not shown, carried by the tractor. A gimbal 93 mounts each of the cylinders 89 in trunnions 86 for universal movement relative thereto.

Referring to Fig. 7, each of the gimbals 93 has a pair of outwardly extending spindles 94 which are pivotally secured to trunnion 86 by a pair of caps 96. Caps 96 are secured to trunnion 86 by bolts 97 and nuts 98. The cylinder 89 has a pair of pivot studs 99 welded thereto and, as shown in Figs. 5 and 6, these studs are pivotally held in the girnbal 93 by a pair of caps 101. Caps 101 are secured to their associated gimbals by bolts 102 and nuts 103.

Referring to Figs. 5 and 6, the upper end of a piston rod 104 is secured to the piston 91. The lower end of the piston rod 104 is pivotally secured to a bracket 106, the latter being welded to the push frame 31.

As shown in Fig. 6, expansion and contraction of the hydraulic jack 92 will lower and raise the blade 34 rela-. tive to the tractor main frame 13. stood that a second hydraulic jack is secured to side wall 42' of the guard 22 and the construction and installation of this second jack is a reverse image of the construction and installation of jack 92 shown in Figs. 5 and 6.

As shown in Fig. 6, the bolts 68 and nuts 69 securing the guard 22 to brackets 24, 24' have been removed and in this condition the guard 22 is free to rotate about its pivots 23, 23'. Contraction of the jacks 92 effects pivoting of the guard about its pivots 23 away from the front of the engine 17. When the guard 22 is pivoted forwardly away from the front end of the engine 17, the components at the forward end of the engine, such as radiator 107, fan 108, hydraulic pump, not shown, water pump, not shown, and other accessories may be removed, installed or serviced by a mechanic or operator. This guard may weigh as much as 1000 pounds and thus a separate power lift such as a crane or overhead winch would normally be needed to lift the guard on and off the tractor. ever, when using the design herein described, once the guard is mounted on the tractor the hydraulic jacks may be used to pivot the guard forwardly to permit servicing and replacement of the components at the front end of the engine. Expansion of the jacks swings the guard to an upright position in which it may again be attached. to the stabilizing braces 24, 24'.

The guard described herein is not only pivoted to the main frame, but also carries power operated lift means for controlling pivotal adjustment of a tool such as a bulldozer blade. Releasable bracing means such as brace 24, 24', bolts 68 and nuts 69 prevent the guard from pivoting when they are secured and permit pivoting when released.

In addition to the advantages afforded by a pivotally mounted guard which mounts the power operated lift means, the dozer lift jacks 92 of the embodiment shown in Figs. 5, 6 and 7 may be employed to pivot the guard to and from an installed position.

It should be understood that it is not intended to limit the invention to the particular forms and details described herein and that the invention includes such other forms and modifications as are embraced by the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. In combination with a vehicle having a main frame supporting an engine: a guard having a vertically disposed front wall, a pair of laterally spaced side walls and a top wall, said walls being rigidly interconnected to form a It should be under-.

How-

shell in protective relation to one end of said engine; a load pivot connection for supporting said guard upon said main frame and permitting pivotal movement of said guard about a first transverse pivot axis, a pa rof stub shafts forming part of said pivot connection, being rigidly mounted respectively on opposite lateral sides of said main frame in-axial alignment on said axis and presenting a pair of upward facing arcuate bearing surfaces, a pair of bracket elements forming another part of said pivot connection being rigidly secured, respectively, to the lower portion of said side walls and presenting a pair of downward facing arcuate bearing surfaces concentric with said axis'and complementary to and rotatably mounted on said upward facing bearing surfaces, a pair of cap elements underlying said stub shafts respectively, means for detachably fastening said caps respectively on said bracket elements in cooperative relation with said stub shafts thereby securing the latter in load bearing relationship with said bracket elements; attaching means releasably connecting said guard to said main frame independently of said pivot connection; a tool pivotally mounted on said vehicle for vertical swinging movement about a second transverse axis including a blade portion disposed forwardly of said front end of said main frame; and a pair of double acting hydraulic jacks having corresponding ends pivotally connected to said guard and tool respectively, said jacks being operable to rotate said guard about said pivot axis upon release of said attaching means.

2. In combination with a vehicle having a main frame supporting an engine adjacent one end thereof: a guard having a vertically disposed front wall, a pair of laterally spaced side walls and a top wall, said walls being rigidly interconnected to form a shell in protective relation to one end of said engine; a load transmitting pivot connection for supporting said guard upon said main frame at opposite lateral sides respectively and permitting pivotal movement of said guard about a first transverse axis, a pair of stub shafts forming part of said pivot connection being rigidly connected, respectively, on opposite lateral sides of said main frame in axial alignment on said transverse axis and presenting a pair of cylindrical upward facing bearing surfaces, a pair of bracket elements rigidly mounted, respectively, on the lower portion of said side walls forming part of said pivot connection and each having a first cylindrical recess concentric with said axis, each of said recesses presenting a downward facing bearing surface complementary to and rotatably mounted, respectively, on said upward facing cylindrical bearing surfaces, a pair of cap members, respectively, presenting a second cylindrical recess being concentric with said first recess, said caps being secured respectively to said bracket elements in underlying relationship to said stub shafts, means for detachably fastening said caps upon said bracket elements in cooperative relation with said stub shafts, respectively, thereby securing the latter in said first and second recesses; a pair of braces attached to opposite sides of said main frame, respectively, independent of said pivot connection and each having a portion extending upwardly from said main frame, means releasably securing said portion of said braces to the rearward edges of said side walls respectively: vertically disposed side panels extending in longitudinal relation to said main frame and having their lower edges secured to opposite sides of said main frame respectively; and means releasably securing said portions of said braces to the forward edges of said side panels respectively, a tool pivotally mounted on said vehicle for vertical swinging movement about a second transverse axis including a blade portion disposed forwardly of said front end of said main frame; and power operated lift means operatively interposed between said guard and said tool for controlling the pivotal adjustment of said tool about said second transverse axis.

3. In combination with a vehicle having a main frame supporting an engine adjacent one end thereof: a guard for one end of said engine having a pair of laterally spaced side walls and a top. wall rigidly interconnecting saidside walls; a load transmitting pivot connection for supporting said guard upon said main frame and perpivot'connection, being mounted on the main frame,

and having an arcuate bearing surface matching the arcuate bearing surface of said first load transmitting element; means for releasably maintaining said first and second load transmitting elements in complementary load bearing relationship; attaching means releasably securing said guard to said main frame independently of said pivot connection; a tool pivotally mounted on said.

vehicle for vertical swinging movement about a second transverse axis including a blade portion disposed outwardly of said one end of said main frame; and power operated lift means operatively interposed between said guard and said tool for controlling the pivotal adjustment of said tool about said second transverse axis, said lift means being operable to rotate said guard about said pivot axis upon release of said attaching means.

4. In combination with a vehicle having a main frame supporting an engine: a guard for one end of said engine having a pair of laterally spaced side walls and a top wall rigidly interconnecting said side walls; a load transmitting pivot connection for supporting said guard upon said main frame and permitting pivotal movement of said guard away from said engine about a first transverse pivot axis; a first pair of load transmitting elements forming a part of said pivot connection, being mounted respectively on the lower portion of said side walls and having arcuate bearing surfaces concentric with said first pivot axis; a second pair of load transmitting elements forming complementary parts of said pivot connection being mounted respectively on opposite sides of said main frame and having arcuate bearing surfaces matching said arcuate bearing surfaces of said first pair of load transmitting elements respectively; connecting means for maintaining said first and second pairs of load transmitting elements in complementary load bearing relationship; attaching means releasably securing said guard to said main frame independently of said pivot connection; a tool pivotally mounted on said vehicle for vertical swinging movement about a second transverse axis including a transverse blade portion disposed outwardly from said guard; and a pair of hydraulic jacks having their upper ends pivotally connected respectively to said side walls and their lower ends pivotally connected respectively to said tool, said hydraulic jacks being operable to control pivotal adjustment of said tool about said second transverse axis and to transfer reactive thrust from said tool for effecting pivotal movement of said guard away from said engine upon release of said attaching means.

5. In combination with a vehicle having a main frame: a guard including a vertically disposed outer wall, and a pair of laterally spaced side walls, said walls being rigidly interconnected to form a shield in protective relation to one end of said vehicle; connecting means for attaching said guard on said main frame for pivotal movement about a transverse axis; attaching means releasably securing said guard to said main frame independently of said connecting means; a tool extending outwardly of said one end of the vehicle and being mounted on the latter for pivotal movement on a second transverse axis; and power operated lift means operatively interposed between said guard and said tool for controlling pivotal adjustment of the latter about said second transverse axis, the line of force transmitted between said guard and tool by said power operated lift means passing said vehicle whereby upon release of said attaching means said power means being operative to pivot said guard about said first pivot axis. I

3 6. The combination set forth in claim 5 wherein-said power operated lift means include a doubleacting hydraulic jack having one end connected on one of said side walls and the other end connected to said tool.

7. In combination with a vehicle having a main frame and an engine adjacent one end thereof: an engine guard including a vertically disposed outer wall,- apair of laterally spaced side walls and a top wall, said walls being rigidly interconnected to form a shield in protective relation to oneend of said engine; connecting means for attaching the lower portion of said side walls respectively on said main frame for pivotal movement about a first transverse axis; attaching means releasably securing said guard to said main frame independently of said/connecting means; aground engaging tool ex-1 tending outwardly of said one end'of the vehicle and being mounted on the latter for pivotal movement on asecond transverse axis; and power opera'ted lift means operatively interposed between said guard and said tool for controlling the pivotal adjustment of the latter about said second transverse axis, said liftmeans being operable to rotate said guard about said first pivot axis away from said one end of the engine upon release of said attaching means. s

References Cited in the file of this patent UNITED STATES PATENTS Westfall Mar. 13, 1956 

